[Devel] [PATCH hci-8.1 0/2] vfio, exec: two mainline fixes that Oracle carries

[Konstantin Khorenko <khorenko@virtuozzo.com>]

Two mainline fixes, independent of the MADV_DOEXEC series, found while
comparing our tree with UEK8. Both are in linux-6.12.y as well and
apply to the 211.52.1.22.x branch directly.

- 1: vfio_mig_get_next_state() spins forever under the driver's state
  mutex when userspace asks for the blocked arc STOP_COPY -> PRE_COPY.
  Reproduced with the mtty sample driver: a soft lockup before, EINVAL
  after.
- 2: do_close_on_exec() ran under exec_update_lock, so a FUSE daemon
  that inspects the exec'ing process (for example /proc/PID/maps) from
  its FLUSH handler deadlocked exec. Reproduced with a small FUSE
  filesystem: a deadlock before, a normal exec after.

Tested on a debug kernel: both reproducers, selftests/exec, a Container
start/exec/stop.

https://virtuozzo.atlassian.net/browse/VSTOR-150235

---
Jann Horn (1):
      ms/exec: do_close_on_exec() before taking exec_update_lock

Junrui Luo (1):
      ms/vfio: prevent infinite loop in vfio_mig_get_next_state() on blocked arc

 drivers/vfio/vfio_main.c |  3 ++-
 fs/exec.c                | 22 ++++++++++++++--------
 2 files changed, 16 insertions(+), 9 deletions(-)
---
base-commit: defa968cbe8c38f1ff0231042dee07f00d27b2c9
change-id: 20261014-b4-prep-khorenko-vstor-149847-6-vfio-exec-ms-backports-0564f1b9331f

Best regards,
--  
Konstantin Khorenko <khorenko@virtuozzo.com>

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